Answer:
E) Improve membrane fluidity
Explanation:
Cholesterol constitutes the basic structural element of the skeleton of cell membranes. Without their reinforcement, the membranes would become extremely fluid and lose their consistency. Cholesterol is found in the esterified membranes in its hydroxyl group (OH): with fatty acids, mainly oleic and linoleic, or as cholesterol sulfate. The cholesterol-sulfate polar group is disposed on one of the faces of the membrane that interacts with other polar groups in that area, while its bulky hydrophobic portion is embedded between the apolar parts of the lipids that form the membrane skeleton and They fulfill many other functions, among which the reduction in the permeability of protons and sodium ions, and their participation in signal transmission. Cholesterol is also essential in phagocytosis processes carried out by cells to capture many nutrients and, in general, for the function of cleaning up organic waste produced by macrophages.
The membranes must have a fluid structure so that the integrated proteins can move "horizontally" to interact with their ligands and with other proteins. The fluidity is given by unsaturated fat. With the excess of saturated fat, the membranes become rigid, but only with the necessary unsaturated fat the membranes are extremely fluid and very sensitive to temperature changes. Cholesterol stabilizes the structure of the membranes; In order for them to have the correct structure, they must have the correct proportions of saturated, unsaturated fats and cholesterol. The membranes produced in the laboratory without cholesterol are unstable to temperature changes, drastically modifying their fluidity against the small temperature changes that occur in the physiological range.
In addition to its functions in cell membranes, cholesterol is an important product that metabolism uses as a raw material to make other compounds:
*Bile salts
*Sex hormones
*Hormones of the adrenal cortex (corticosteroids)
*Vitamin D (Calciferol)
Autotrophs make their own food using energy from photosynthesis.
<u>The autotrophs use energy from the sun to convert water from the soil and carbon dioxide from the air into glucose. </u>
Answer:
The answer is B.
Explanation:
When you skin your knee, cells divide to replace old, dead, or damaged cells.
Bellow I attached the punnet square you need. From it you can see, that the likelihood of producing an offspring with attached earlobes is 25% (ff)
The difference between these three types of rock is in their formation process:
• Igneous rocks are formed by thesolidification of melted rocksm(agma) inside the Earth.
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• Metamorphic rocks are formed from the other types of rock that suffer changes due to different processes,for examples caused by high preasures or heat.
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• Sedimentary rocks are formed by the accumulation
